Sweeping machines



Oct. 27, 1970 J. H. ERIKSSON 3,535,731

SWEEPING MACHINES Filed Feb. 1, 1968 2 Sheets-Sheet 1 FIG. I

m v E- NTOR: JOHN HERBERT E-RrKssorv Oct. 27, 1970 J. H. ERIKSSIOCN 3,535,731

SWEEPING MACHINES Filed Feb. 1, 1968' 2 Sheets-Sheet 2 lNva- ToQ: JOHN HERBERT ERIKSSON United States Patent 3,535,731 SWEEPING MACHINES John Herbert Eriksson, Fagelsangen, Ronninge, Sweden Filed Feb. 1, 1968, Ser. No. 702,281 Claims priority, application Norway, Mar. 29, 1967, 167,467 Int. Cl. E01h 1/04 US. Cl. 15-340 6 Claims ABSTRACT OF THE DISCLOSURE A sweeping machine has at least one brush assembly and a dust separator associated therewith for separating the dust from the dust-laden air whirled up by the brush assembly during sweeping.

This invention relates to an improved sweeping machine having at least one brush assembly for sweeping together waste matter such as refuse, gravel, mud etc. encumbering roadways and like surfaces and for placing the waste matter in a strand or in stacks on or adjacent the roadway, from where the waste matter is collected by a selfloading machine propelled behind the sweeping machine.

The present invention has for its object to provide a sweeping machine with means for reducing the dust formation which is so very dangerous from the viewpoint of road safety and arises when roadways and streets are swept by non-selfloading sweeping machines. Characteristic of the sweeping machine of the invention is that the brush assembly has associated with it a dust separator which is adapted, without unfavourably affecting the sweeping operation, to separate the dust from the dustladen air whirled up by the brush assembly.

For better elucidation the invention will be described more fully in the following with reference to the accompanying diagrammatic drawings in which:

FIG. 1 shows a side elevation of a first embodiment of an improved sweeping machine according to the present invention;

FIG. 2 shows a side elevation of a second embodiment of such sweeping machine.

A rotary cylinder brush assembly 1 of the sweeping machine is mounted in a U-shaped member 2 which is supported by a frame 3 connected to the draft vehicle. The U-shaped member 2 is pivoted to the frame 3 and can be adjusted together with the brush assembly at various angles to the dierction of propulsion and also be raised from the roadway. The brush assembly 1 can be driven from the power take-off of the draft vehicle or by any other suitable power source.

In accordance with the invention, the sweeping machine comprises a dust separator. In the embodiment illustrated in FIG. 1, the dust separator comprises a housing 4 which embraces the brush assembly 1 and which at the lower edge facing the ground has an elastic trailing skirt 5 which serves as a seal with respect to the roadway. At the part of the housing 4 which during sweeping will be situated in or adjacent the flow of swept material there are provided one or more suction nozzles 6. The suction nozzles 6 are connected to a fan 7 which sucks up the dust-laden air from the interior of the housing 4 into which clean air is continuously sucked in along the lower edge of the elastic trailing skirt. The fan 7 blows the dust-laden air through the dust separator 8 from which the cleansed air escapes in a free upward flow through the tube 9. The dust separator 8 in this embodiment is a cyclone but may also be a filter unit of any suitable kind. The relatively compact dust separated from the dust-laden air falls down into a container 10. The discharge tube 11 of the container being rotatable and telescopic, the

mouth 11a of the tube can be set into different positions for discharge of the separated dust onto the roadway ahead of the cylinder brush to be mixed with the nondusting coarse particles and to be supplied to the swepttogether strand of refuse without any appreciable dust formation, or laterally of the cylinder brush into said strand of refuse. The separated dust can also be collected in the container 10 for batchwise emptying therefrom.

To avoid that dust whirls up through the mouth 11a of the discharge tube 11, when the dust is not collected, there can be provided a portion dispensing means 12 e.g. in the shape of a weight-loaded door. Of course, such device is not absolutely necessary, and the dust can be allowed to stream continuously direct from the mouth 11a of the dust separator discharge tube 11.

To permit use of the sweeping machine illustrated in FIG. 1 also for snow clearing and other uses where no dust separation is necessary and there is a risk that snow, mud and other matter will collect in the housing and clog the nozzles, the housing is sodesigned as to permit simple dismounting thereof from the sweeping machine together with the nozzles and related components of the dust separator.

In the sweeping machine illustrated in FIG. 2 the rotary cylinder brush assembly 1 is mounted in a U-shaped member 2 like in the earlier embodiment. As before, the U-shaped member is supported by a frame connected to the draft vehicle and suitably carried thereby. Preferably, the brush is mounted for relative vertical move ment with respect to the housing, and the brush is normally resiliently urged by suitable spring means toward the roadway. Also in this embodiment, the brush assembly 1 is arranged for pivotment in relation to the draft vehicle together with the U-shaped member and preferably also the frame, so that the brush assembly can be adjusted at various angles to the direction of propulsion to permit deposit of swept-together matter towards any desired side, it being of course also possible to raise the brush assembly out of engagement with the roadway for transportation. For the operation of the brush assembly use can be made also in this case of the power take-01f of the draft vehicle, a separate motor or other power source.

In the embodiment illustrated in FIG. 2, the dust separator of the sweeping machine according to the invention comprises a downwardly open housing 4 which embraces the brush assembly 1 and which is vertically movable with the aid of links 13 in relation to the U-shaped member 2 and the frame 3. The housing 4 has supporting wheels 14 which run on the roadway and ensure that the lower edge of the housing will always be close to the surface of the roadway irrespective of the change of position that the brush assembly undergoes when it is gradually lowered due to wear. To attain the best possible seal against the roadway along the lower edge of the housing an electric skirt 5 is mounted at said lower edge. Within the front portion of the housing, against which the swept-up matter will be thrown, there is mounted a filter device 15 which is in communication over a conduit 16, having a resilient intermediary member inserted therein, with the suction fan 7 from which the cleansed air escapes through the tube 9. A bafiie 17 is arranged between the filter device 15 and the brush assembly 1, and the object of said bafiie is to prevent that in moist weather mud and wet dirt is thrown upward onto the filter device, whereby the function thereof may be jeopardized.

In the embodiment shown the filter device 15 is a tubular filter sleeve which is preferably folded in bellows: shapeand passed onto a body provided with suitable throughflow apertures. The material of the filter may be metal, textile or synthetic fibres, or combinations of these materials. The embodiment illustrated does not comprise a particular cleaning device for the filter discharge means for the collected dust, as it is intended that the dust collecting in the form of clods or cakes on the filter surface shall fall by gravity into the coarse matter swept together by the brush assembly and to be mixed therewith during the discharge thereof towards either side. Alternatively, the filter may be cleaned as by vibration, washing, or by reversing the flow of air therethrough. If it is considered less desirable to have the separated dust mixed with the collected coarse matter an upwardly open screw conveyor or like means can be disposed in the housing beneath the filter, the dust falling into said screw conveyor so as to be discharged at one end wall of the housing either into a container or into the swept-together strand of matter deposited alongside the roadway.

In a modification (not shown) of the embodiment illustrated in FIG. 2 the fan 7 also is disposed at the housing 4 embracing the brush assembly so that the dust separator and said housing form a unit which can be readily dismounted from the sweeping machine when the machine is used e.g. for snow clearing purposes.

In neither embodiment is there shown a drive for the fan since the latter can be driven in many different ways e.g. from the power take-off of the draft vehicle, by a separate motor or by any other power source.

While two embodiments of the invention have been described in the foregoing and shown in the accompanying drawings, those skilled in the art will readily realize that the invention can be modified in several ways within the scope of the appended claims.

What I claim and desire to secure by Letters Patent is:

1. In a sweeping machine of the type employing a driven rotary brush assembly to sweep waste material into a windrow as the machine traverses a surface to be swept, the improvement comprising a dust separator for removing dust particles from the air surrounding the machine, which dust particles are undesirably and unavoidably whirled up by the rotary movement of said brush, dust separator including an upwardly concave housing member having an open bottom disposed over and embracing said brush assembly, an opening in said housing, an air filtration unit, a conduit operably connecting said air filtration unit and said opening, an exhaust fan connected to said conduit for withdrawing dust-laden air from beneath said housing through said air filtration unit to filter dust particles therefrom during operation of the sweeping machine, said opening being positioned in said housing to permit operation of said dust separator without interfering with operation of said sweeping machine to sweep material into a windrow on the surface of a roadway, said air filtration unit of the dust separator being disposed adjacent said opening in said housing embracing the brush assembly, the dust-laden air within the housing being sucked by said fan towards and through a filter surface of said filtration unit directed toward the interior of said housing so that the filtered dust is retained by said filter surface while the cleansed air is evacuated from said housing, and baffie means mounted within said housing between said opening and said brush to prevent material from being thrown by said brush onto said filter surface.

2. A sweeping machine as defined in claim 1, in which said housing, said filtering unit, and said fan, are mounted as a unit on the sweeping machine so that said dust separator assembly comprising the said components can be removed from the sweeping machine to permit operation thereof independently of said dust separator.

3. In a sweeping machine of the type employing a driven rotary brush assembly to sweep waste material into a windrow as the machine traverses a surface to be swept, the improvement comprising a dust separator for removing dust particles from the air surrounding the machine, which dust particles are undesirably and unavoidably whirled up by the rotary movement of said brush, said dust separator including an upwardly concave housing member having an open bottom disposed over and embracing said brush assembly, an opening in said housing, an air filtration unit, a conduit operably connecting said air filtration unit and said opening, an exhaust fan connected to said conduit for withdrawing dustladen air from beneath said housing through said air filtration unit to filter dust particles therefrom during operation of the sweping machine, said opening being positioned in said housing to permit operation of said dust separator without interfering with operation of said sweeping machine to sweep material into a windrow on the surface of a roadway, said air filtration unit of the dust separator being disposed adjacent said opening in said housing embracing the brush assembly the dustladen air within the housing being sucked by said fan towards and through a filter surface of said filtration unit so that the filtered dust is retained by said filter surface while the celanser air is evacuated from said housing, means for celaning said filter surface, the rust collected on said filter surface being permitted to fall by gravity from the filter surface onto the windrow of waste material swept together by said brush.

4. In a swetping machine of the type employing a driven rotary brush assembly to sweep waste material into a windrow as the machine traverses a surface to be swept and a dust separator operable to remove dust particles from the air surrounding the brush assembly during operation thereof, which dust particles are undesirably and unavoidably whirled up by the rotary movement of the brush, the improvement wherein said dust separator comprises an upwardly concave housing member having an open bottom disposed over and embracing said brush assembly, an opening in said housing, an air filtration unit, a conduit operably connecting said air filtration unit and said opening, an exhaust fan connected to said conduit and operable to withdraw dust-laden air from beneath said housing through said air filtration unit to filter dust particles therefrom during operation of the sweeping machine, said opening being positioned in said housing to permit operation of said dust separator without interfering with operation of said sweep material into a windrow on the surface of a roadway, said air filtration unit being disposed adjacent said housing embracing the brush assembly, and means for directing dust separated by said filtration unit from said dust separator back to the surface being swept in position to be mixed with waste material swept into a windrow by said brush assembly.

5. In a sweeping machine as defined in claim 4, the further improvement wherein said means for directing dust collected by said filtration unit is adjustable to permit the separated dust to be deposited in different positions on the roadway relative to said brush.

6. In a sweeping machine of the type defined in claim 5, the further improvement wherein said means for directing rust separated by the filtration unit conveys the separated dust directly onto a windrow swept together by the machine.

References Cited UNITED STATES PATENTS 1,301,927 4/1919 Frame 1s 32 913,396 4/1909 N06.

913,460 2/1909 Bishop 1s -340 1,085,676 2/1914 Finch 15 349 1,107,564 3/1914 Ward 15 340 ROBERT w, MICHELL, Primary Examiner US. Cl. X.R. 15352 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 53 1731 Dated October 27; 1970 lnvent fl John Herbert Eriksson It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, lines 21 and 58, delete "rust" and insert --dU.St--w MEI-MM WILLIAM E. saaumm. .m- Mlflflflt Gomissioner of Patents FORM 904050 USCOMM-DC wan-Poe "Ti, GOVERNMENT PI 'I'HNG OFFICE I 1.. O:. ,,l 

